The ascomycete Trichoderma reesei is a paradigm for the regulation and production of plant cell wall-degrading enzymes, including xylanases. Four xylanases, including XYN1 and XYN2 of glycosyl hydrolase family 11 (GH11), the GH10 XYN3, and the GH30 XYN4, were already described. By genome mining, we identified a fifth xylanase, XYN5, belonging to GH11. Transcriptional analysis reveals that the e...

Reports on the bacterial utilization of u-arabinose have shown two pathways of dissimilation. The first, reported by Cohen (l), demonstrated that Escherichia coli first isomerized n-arabinose to n-ribulose, which was then phosphorylated. A later report by Doudoroff et al. (2) showed that Pseudomonas saccharophi&a oxidized n-arabinose to n-arabonolactone, which was subsequently hydrolyzed to the...

The exopolysaccharide (EPS) and capsular polysaccharide (CPS) composition of four Azospirillum brasilense strains differing in their aggregation capacity was analyzed by high performance anion exchange chromatography. When growing the different strains in an aggregation inducing medium containing a high carbon:nitrogen (C:N) ratio, both EPS and CPS showed a positive correlation between aggregat...

Effects of excess concentrations of boron on major cell wall components of tobacco cells(Nicotiana tabacum L. cv. Burley 21) were studied. Pectin, xyloglucan, hydroxyproline-richglycoproteins (extensin), and arabinogalactan proteins were characterized. Results showedthat increased boron supply resulted in significant decrease in cell and cell wall dry weights.Also, high concentrations of boron ...

Arabinosylation of hydroxyproline (Hyp) is a post-translational modification often found in secreted peptide signals in plants. The physiological importance of this modification was highlighted by the finding that CLAVATA3 (CLV3), a key peptide signal for regulating the fate of stem cells in the shoot apical meristem in Arabidopsis, contains three l-arabinose residues linked via linear β-1,2-li...

BACKGROUND L-Arabinose is a non-caloric sugar, which could affect glucose and lipid metabolism and suppress obesity. However, few reports have described the effect of L-arabinose in metabolic syndrome, a combination of medical disorders that increase the risk of diabetes and cardiovascular disease. OBJECTIVE This study was conducted to explore the effects of L-arabinose in rats with metabolic...

A glucose, xylose and arabinose utilizing Zymomonas mobilis strain was constructed by incorporating arabinose catabolic pathway genes, araBAD encoding L-ribulokinase, L-arabinose isomerase and L-ribulose-5-phosphate4-epimerase in a glucose, xylose co-fermenting host, 8b, using a transposition integration approach. Further improvement on this arabinose-capable integrant, 33C was achieved by appl...

The 2,3,4-tri-toluenesulfonate ester derivatives of the methyl pyranosides of l-arabinose, d-ribose, d-lyxose, and d-xylose have been prepared, and their substitution reactions with various nucleophiles have been examined. For arabinose, xylose, and ribose, highly regioselective monosubstitutions were observed with benzoate, nitrite, and azide anions. These reactions have led to short and simpl...

D-Galactose, which did not serve as a growth substrate, was found to induce an L-arabinose isomerase of similar properties to the L-arabinose-induced L-arabinose isomerase. In both cases the pH profiles, pH stability, optimum temperature, heat stability, substrate specificity, metal ion requirements, mobility on polyacrylamide gel electrophoresis, and kinetic properties of the induced isomerase...

BACKGROUND Cost-effective fermentation of lignocellulosic hydrolysate to ethanol by Saccharomyces cerevisiae requires efficient mixed sugar utilization. Notably, the rate and yield of xylose and arabinose co-fermentation to ethanol must be enhanced. RESULTS Evolutionary engineering was used to improve the simultaneous conversion of xylose and arabinose to ethanol in a recombinant industrial S...